Endophyte ergot alkaloid synthetic compounds, compounds which encode therefor and related methods

The present invention provides, inter alia, dmaW nucleic acid sequences and the proteins for which they encode. Also provided are methods for the utilization of knockout mutants of the sequences which are useful for engineering ergot alkaloid-deficient fungal symbionts (endophytes) of plants. Other methods and materials related to these sequences are also provided.

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Description

This application claims priority to U.S. Provisional Patent Application Serial No. 60/125,490, which was filed on Mar. 22, 1999.

The present invention was funded in part by USDA NRI grant 95-37303-1678; the U.S. Government may have certain rights in this invention.

FIELD OF THE INVENTION

The present invention relates to sequences that encode dimethylallyl-diphosphate:L-tryptophan dimethylallyltransferase (“DmaW” or “dimethylallyltryptophan synthase”), an enzyme present in some grass endophytes, and that catalyzes the formation of 4- &ggr;,&ggr;-dimethylallyltryptophan. This enzyme activity is the first committed step in the production of ergot alkaloids, including those with clavine and ergoline-ring structures. Such alkaloids include clavines, lysergic acid, lysergic acid amides, and ergopeptines. The sequences encode a DmaW from fungi that are symbionts of commercially significant grasses.

BACKGROUND OF THE INVENTION

Certain fungal species exist as symbiotic and integral parts of grasses and are passed from generation to generation of plants, but many are not passed from plant to plant except by transmitting in seeds of maternal plant lineages. Representatives of these fungi are the Neotyphodium species (“Neotyphodium” and sometimes “Acremonium”, for example, N. coenophialum) and Epichloe species (e.g. E. festucae and E. typhina), which are symbionts and integral parts of many grass cultivars. These fungi, termed “endophytes”, are seed-transmissible at extremely high efficiency. Their symbioses with host grasses are characterized by mutual benefits to the hosts and symbionts. Benefits to the grass hosts include protection from insects and vertebrates, and resistance to water stress (drought). Anti-insect activities are mainly due to pyrrolopyrazine and pyrrolizidine alkaloids produced by the endophytes. Anti-vertebrate activities are mainly due to indole alkaloids, including the ergot alkaloids (clavines, lysergic acid and its derivatives, and ergopeptines).

Tall fescue is grown on over 14 million hectares as an important forage, turf and conservation grass; most of the tall fescue grown in the U.S. contains ergot-alkaloid-producing endophytes. The anti vertebrate activity of the ergot alkaloids, which manifests as “tall fescue toxicosis” in cattle and other livestock, causes losses estimated at more than $600 million per year.

In 1992, Gebler and Poulter purified the DmaW enzyme from Claviceps sp. ATCC 26245 to a single protein band observable by SDS-PAGE electrophoresis, and fragmented the protein with CNBr. Gebler et al., 114 Journal of the American Chemical Society 7354 (1992). The three resulting fragments were purified and their N-termini sequenced. In research by one of the inventors of the present invention, there was disclosed a sequence of a dmaW gene (herein dmaW) from C. fusiformis ATCC 26245 organism from which the sequence was identified was mis-named C. purpurea by the supplier to the ATCC, and was actually C. fusiformis.) Tsai et al., 216 Biochem & Biophys Res Comm 119 (1995). The C. fusiformis sequence from that research is 58% identical to the present sequences at the DNA level. More recently, a C. purpurea dmaW sequence was disclosed in Tudzynski et al., 261 Molec Gen Genet 133 (1999), and is 62% identical at the DNA level to the present sequence.

Citation of the above documents is not intended as an admission that any of the foregoing is pertinent prior art. For example, in some instances above, the publication was less than one year before the filing date of this patent application. All statements as to the date or representation as to the contents of these documents is based on subjective characterization of information available to the applicant at the time of filing, and does not constitute an admission as to the accuracy of the dates or contents of these documents.

SUMMARY OF THE INVENTION

It is therefore an object of the present invention to provide sequences useful to engineer ergot alkaloid-deficient symbionts, thus ergot-alkaloid-deficient plants.

It is a further object to provide methods to engineer ergot alkaloid-deficient endophytes.

It is yet another object to provide ergot alkaloid-deficient seeds.

It is yet another object to provide plants with ergot alkaloid-deficient endophytes.

It is also an object of the invention to provide materials such as vectors for engineering ergot alkaloid-deficient endophytes.

It is also an object of the invention to provide enzymes useful in ergot alkaloid synthesis.

Also, it is an object to use the present nucleic acid compounds to determine the potential or lack of potential of symbiont strains to produce ergot alkaloids.

Other objects will be apparent from the present disclosure.

Definitions:

For the purposes of the present application, the following terms have the following meanings. All other terms have the meaning as specifically recognized in the art.

“Allelic variant” is meant to refer to a full length gene or partial sequence of a full length gene that occurs at essentially the same locus (or loci) as the referent sequence, but which, due to natural variations caused by, for example, mutation or recombination, has a similar but not identical sequence. Allelic variants typically encode proteins having similar activity to that of the protein encoded by the gene to which they are being compared. Allelic variants can also comprise alterations in the 5′ or 3′ untranslated regions of the gene (e.g., in regulatory control regions).

“Fragment” is meant to refer to any subset of the referent nucleic acid sequence.

“Knockout construct” means a DNA sequence which has been altered via any known means, for example, deletion, insertion, point mutation or rearrangement, so as to alter or eliminate the function of the naturally-occurring sequence product, but not so as to alter the ability of the DNA sequence to recombine with the naturally-occurring sequence.

“Knockout mutants” are cells, embryos, fungi or plants in which a naturally-occurring dmaW sequence has been replaced through genetic engineering with a knockout construct, so as to result in a ergot alkaloid-deficient phenotype, especially a dimethylallyl-diphosphate:L-tryptophan dimethylallyltransferase- deficient phenotype.

“Proteins” means any compounds which comprise amino acids, including peptides, polypeptides, fusion proteins, etc.

Moreover, for the purposes of the present invention, the term “a” or “an” entity refers to one or more of that entity; for example, “a protein” or “a nucleic acid molecule” refers to one or more of those compounds or at least one compound. As such, the terms “a” (or “an”), “one or more” and “at least one” can be used interchangeably herein. It is also to be noted that the terms “comprising”, “including”, and “having” can be used interchangeably. Furthermore, a compound “selected from the group consisting of” refers to one or more of the compounds in the list that follows, including mixtures (i.e., combinations) of two or more of the compounds. According to the present invention, an isolated, or biologically pure, protein or nucleic acid molecule is a compound that has been removed from its natural milieu. As such, “isolated” and “biologically pure” do not necessarily reflect the extent to which the compound has been purified. An isolated compound of the present invention can be obtained from its natural source, can be produced using molecular biology techniques or can be produced by chemical synthesis.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 schematically depicts the first step of the herein-described indirect gene replacement.

FIG. 2 schematically depicts the second step of the herein-described indirect gene replacement.

FIG. 3 schematically depicts the herein-described homologous gene replacement.

FIG. 4 schematically depicts the alternative life cycles of Epichloe and Neotyphodium species in host grasses.

DETAILED DESCRIPTION OF THE INVENTION

The present invention provides, inter alia, isolated nucleic acid molecule encoding a DmaW sequence, wherein said nucleic acid molecule comprises a nucleic acid sequence selected from the group consisting of:

(a) a nucleic acid sequence which has more than 63% identity to a sequence selected from the group consisting of SEQ ID NO 1 and SEQ ID NO 3, and wherein said identity can be determined using the DNAsis computer program and default parameters;

(b) a nucleic acid molecule selected from the group consisting of: a nucleic acid molecule which encodes a DmaW amino acid sequence selected from the group consisting of: SEQ ID NO 2; SEQ ID NO 4; a protein encoded by an allelic variant of SEQ ID NO 1; and a protein encoded by an allelic variant of SEQ ID NO 3.

Allelic variants, fragments (including a portion of a molecule) and homologues are, by definition of “nucleic acid molecule”, included within this and other embodiments.

Included within the scope of the present invention, with particular regard to the nucleic acids above, are allelic variants, degenerate sequences and homologues. Allelic variants are expected to be found in nature. The present invention also includes variants due to laboratory manipulation, such as, but not limited to, variants produced during polymerase chain reaction amplification or site-directed mutagenesis. It is also well known that there is a substantial amount of redundancy in the various codons which code for specific amino acids. Therefore, this invention is also directed to those nucleic acid sequences which contain alternative codons which code for the eventual translation of the identical amino acid. Also included within the scope of this invention are mutations either in the nucleic acid sequence or the translated protein which do not substantially alter the ultimate physical properties of the expressed protein. For example, substitution of valine for leucine, arginine for lysine, or asparagine for glutamine may not cause a change in functionality of the polypeptide. Lastly, a nucleic acid sequence homologous to the exemplified nucleic acid molecules (or allelic variants or degenerates thereof) can have approximately 85%, preferably approximately 90%, and most preferably approximately 95% sequence identity with a nucleic acid molecule in the sequence listing.

Stringent hybridization conditions are determined based on defined physical properties of the gene to which the nucleic acid molecule is being hybridized, and can be defined mathematically. Stringent hybridization conditions are those experimental parameters that allow an individual skilled in the art to identify significant similarities between heterologous nucleic acid molecules. These conditions are well known to those skilled in the art. See, for example, Sambrook, et al., 1989, Molecular Cloning: A Laboratory Manual, Cold Spring Harbor Labs Press, and Meinkoth, et al., 1984, Anal. Biochem. 138, 267-284.

It is known in the art that there are commercially available computer programs for determining the degree of similarity between two nucleic acid sequences. These computer programs include various known methods to determine the percentage identity and the number and length of gaps between hybrid nucleic acid molecules. Preferred methods to determine the percent identity among amino acid sequences and also among nucleic acid sequences include analysis using one or more of the commercially available computer programs designed to compare and analyze nucleic acid or amino acid sequences. These computer programs include, but are not limited to, GCG™ (available from Genetics Computer Group, Madison, Wis.), DNAsis™ (available from Hitachi Software, San Bruno, Calif.) and MacVector™ (available from the Eastman Kodak Company, New Haven, Conn.). A preferred method to determine percent identity among amino acid sequences and also among nucleic acid sequences includes using the Compare function by maximum matching within the program DNAsis Version 2.1 using default parameters.

In one embodiment of the present invention, a preferred dmaW nucleic acid molecule includes an isolated nucleic acid molecule which is at least about 50 nucleotides, or at least about 150 nucleotides, and which hybridizes under conditions which preferably allow about 25% base pair mismatch, more preferably under conditions which allow about 20% base pair mismatch, more preferably under conditions which allow about 15% base pair mismatch, more preferably under conditions which allow about 10% base pair mismatch and even more preferably under conditions which allow about 5% base pair mismatch with a nucleic acid molecule selected from the group consisting of SEQ ID NO 1 and SEQ ID NO 3.

Another embodiment of the present invention includes a nucleic acid molecule comprising at least about 150 base-pairs, wherein the nucleic acid molecule hybridizes, in a solution comprising 1X SSC and 0% formamide, at a temperature of about 56° C., to a nucleic acid sequence selected from the group consisting of: SEQ ID NO 1 and SEQ ID NO 3. Also preferred are fragments of any of such nucleic acid molecules.

Additional preferred dmaW nucleic acid molecules of the present invention include an isolated nucleic acid molecule which is at least about 50 nucleotides, or at least about 150 nucleotides, comprising a nucleic acid sequence that is preferably at least about 65% identical, more preferably about 70% identical, more preferably about 75% identical, more preferably about 80% identical, more preferably about 85% identical, more preferably about 90% identical and even more preferably about 95% identical to a nucleic acid sequence selected from the group consisting of SEQ ID NO 1 and SEQ ID NO 3. Also preferred are fragments of any of such nucleic acid molecules. Percent identity may be determined using the Compare function by maximum matching within the program DNAsis Version 2.1 using default parameters.

Vectors which comprise the above molecules are within the scope of the present invention, as are endophytes and other fungi transformed with the above sequences as are plants having endophytes transformed with the above sequences. Vectors may be obtained from various commercial sources, including Clontech Laboratories, Inc. (Palo Alto, Calif.), Stratagene (La Jolla, Calif.), Invitrogen (Carlsbad, Calif.), New England Biolabs (Beverly, Mass.) and Promega (Madison, Wis.).

Preferred vectors are those which are capable of transferring the molecules disclosed herein into fungal cells. A vector which provided for either an early or late promoter in conjunction with the present sequences would be useful in certain circumstances. For instance, the following promoters would be useful in early expression of the present sequences:

glyceraldehyde-3-phosphate dehydrogenase gene promoter [Jungehülsing et al., 25 Current Genetics 101 (1994)].

trpC promoter [Yelton et al., 82 Proceedings of the National Academy of Sciences of the United States of America 834 (1985)].

beta-tubulin gene promoter [Tsai et al., 22 Current Genetics 399 (1992)].

These are fungal promoters that are known to work in endophytes or (for the glyceraldehyde-3-phosphate dehydrogenase gene promoter) the related fungus Claviceps purpurea.

In order to then constitutively express the sequences described above, the construct optionally contains, for example, a beta-tubulin promoter according to the proceedures in Tsai et al., 22 Current Genetics 399 (1992).

Moreover, the most commercially significant use of the present invention is in the construction of “knockout mutants” using the above sequences, or known sequences, for design and construction of DmaW-deficient mutants. In other words, the present invention is informative to those skilled in the art as to their usefulness in making the naturally-occurring sequence inactive. For example, the above sequences can be mutated by any means, i.e., deletion, insertion, point mutation, rearrangement, etc, so long as the mutated version or sequences nearby in replicatable DNA of the fungus (e.g. chromosome) retains the ability to recombine. The mutated version of the sequence is then introduced into cells of a preferred line via routine methods (i.e. biolistic processes, electroporation, treatment of wall-less cells with vector, Agrobacterium-mediated transformation, etc.). DmaW-deficient mutants of the preferred line would then be selected and propagated. These “knockout” mutant embryos, seeds and plants are within the scope of the present invention, as are the knockout constructs, i.e. sequences and vectors.

In particular, sequences near the active site of enzyme function, and the site itself, would be preferred targets. Moreover, sequences which are conserved among related organisms are also preferred targets. It is contemplated that a modification of the present invention such that the start codon has been eliminated, or replaced with a stop codon, would be a useful knockout construct. Moreover, excision of the coding region or replacing the coding region with a antibiotic (i.e. hygromycin) resistance gene would be useful. FIGS. 1 through 3 describe examples of such manipulations.

For example, the following seeds, embryos or plants with endophyte transformed with knockout constructs are considered within the present invention. Particularly preferred are: forage, turf and conservation grasses. These include, for example, tall fescue (Festuca arundinacea), meadow fescue (Festuca pratensis), and red fescue (Festuca rubra), which are common turf, conservation (to hold soil and reclaim strip mines) and forage grasses in the U.S. and worldwide. Also used for these purposes, are the ryegrasses such as perennial ryegrass (Lolium perenne). All these have endophytes and most such endophytes produce ergot alkaloids. In particular, tall fescues are most preferred. However, any seed, embryo or plant which comprise endophytes which produce ergot alkaloid is within the scope of the present invention. Of course, those in the art recognize that any seed, embryo or plant with endophyte transformed with knockout constructs which are useful for producing plants for biomass are within the scope of the present invention.

Transformation of cells with the nucleic acid molecules of the present invention can be accomplished according to known procedures. The following procedures are well known: electroporation [Tsai et al., 22 Current Genetics 399 (1992)], treatment of wall-less fungal cells with vector DNA plus CaCl2 and polyethyleneglycol [Yelton et al., 81 Proceedings of the National Academy of Sciences of the United States of America 1470 (1984)], and biolistics [Armaleo et al., 17 Current Genetics 97 (1990)]. In addition, fungi have been transformed using vector-containing bacterial strains, namely Agrobacterium tumefaciens [Gouka et al., 17 Nature Biotechnology 598 (1999)]. The transformed cells are also within the scope of this invention.

The transformed cells may be grown into a fungal mycelium (thallus), which in turn gives rise to spores. Fungal mycelium and spores are propagated indefinitely. In addition, transformed fungal endophyte can be introduced into grass plants. The current preferred method to introduce the fungus into plant is by inoculation of seedling meristems [Latch and Christensen, 107 Annals of Applied Biology 17 (1985)]. Another known method is inoculation and regeneration of plant tissue culture [Johnson et al., 70 Plant Disease 380 (1986)].

Once introduced into a plant the endophyte will remain indefinitely and propagate inside all plant propagules including tillers, stolons, and seeds (unless procedures are undertaken to eliminate live fungal mycelium in the grass, for example by long storage of seeds at ambient temperature). In any grass breeding where the female plant possesses the endophyte the seeds will almost all possess the identical endophyte, and those seeds will give rise to plants with that endophyte [Siegel et al., 74 Phytopathology 932 (1984)]. In this way a grass variety with transformed endophyte can be developed, propagated, and planted for forage, pasture, turf, revegetation, or soil conservation.

Therefore, also provided are methods for constructing sequences with the ability to knockout the above sequences, comprising one of the following techniques: inserting a foreign piece of DNA into one of the disclosed sequences; deleting a piece of DNA from one of the disclosed sequences; or creating a mutation such that the DmaW activity is eliminated.

Also provided are antisense constructs and methods to inhibit translation or accumulation of mRNA transcripts of the disclosed sequences, so as to either eliminate or reduce the amount of sequence product. The procedures for antisense inhibition for mRNA are described in U.S. Pat. No. 5,554,743, which patent is expressly incorporated by reference into this application. Alternatively, the present invention could be used to design ribozymes which specifically cleave dmaW mRNA.

Also provided in the present invention are methods to express or overexpress the dmaW sequences described herein, and using the DmaW in pharmaceutical processes. Ergot alkaloids produced in fungal fermentation or chemically modified ergot alkaloids from fungal fermentation are well known pharmaceuticals. The dmaW gene can be introduced into an ergot alkaloid-producing fungal strain, for example of C. purpurea, thus increasing the copy number and potentially the expression of the DmaW protein. Utilization of a constitutive promoter such as for beta-tubulin [Tsai et al., 22 Current Genetics 399 (1992)] may help increase expression of the gene and, thus, of the protein. Because DmaW catalyzes the rate limiting step of ergot alkaloid synthesis in C. purpurea [Lee et al., 177 Archives of Biochemistry & Biophysics 84 (1976)], its increased expression may increase ergot alkaloid production. The low level of sequence identity between dmaW from different genera (for example between dmaW sequences of Neotyphodium and Claviceps) will reduce the problem known as quenching or cosuppression which limits production of gene products in fungi and plants [Cogoni et al., 65 Antonie Van Leeuwenhoek International Journal of Microbiology 205 (1994)]. Overexpression can be as skill of the art, in particular, according to the procedures described in U.S. Pat. No. 5,477,001.

Also provided in the present invention are methods to identify Neotyphodium or Acremonium or Epichloe fungi that lack dmaW and, therefore, are unlikely to produce ergot alkaloids. The cloned Neotyphodium genes can be used for standard Southern blot hybridization, by anyone skilled in the art, to screen these related fungi for the presence of homologous genes. In addition, degenerate primers can be used for polymerase chain reaction under conditions described to amplify segments of dmaW from fungi in family Clavicipitaceae or from Neotyphodium or Acremonium species. The amplified segments can be analyzed by gel electrophoresis and sequence analysis by anyone skilled in the art. Fungi that lack DmaW can then be introduced into grass plants and thereby incorporated into breeding lines as described above.

Transformation of plant endophytes with these sequences would be according to known procedures as described above. Plants can be grown according to known procedures.

Lastly, the present sequences are useful to identify related sequences, such as those from Balansia, Balansiopsis, Echinodothis, Atkinsonella, Myriogenospora, Neotyphodium, and Parepichloe, or natural or induced mutants. For example, screening could be by Southern blot hybridization analysis of genomic DNA or by polymerase chain reaction using DNA oligonucleotide primers targeted to dmaW or the locus that contains it.

The present invention also provides isolated proteins encoded by a dmaW sequence, wherein said proteins comprise an amino acid sequence selected from the group consisting of:

(a) an amino acid sequence which has more than 68% identity to an amino acid sequence selected from the group consisting of SEQ ID NO 2 and SEQ ID NO 4 and wherein said identity can be determined using the DNAsis computer program and default parameters; and

(b) an amino acid sequence which is encoded by a nucleic acid sequence of claim 1.

There are also provided recombinant cells comprising the nucleic acid molecules and/or proteins herein described.

Proteins which would result from expression of the nucleic acid molecules herein disclosed are preferred, with the proteins which would result from expression of the exemplified nucleic acid molecules being most preferred. It is understood that proteins which would result from expression of allelic variants of the exemplified sequences, as well as proteins which would result from the expression of nucleic acid molecules which hybridize under stringent hybridization conditions to the nucleic acid molecules exemplified are within the scope of the present invention as well. Lastly, an amino acid sequence substantially homologous to a referent dmaW-encoded protein will have at least 85% sequence identity, preferably 90%, and most preferably 95% sequence identity with the amino acid sequence of a referent dmaW-encoded protein or a peptide thereof. For example, an amino acid sequence is substantially homologous to dmaW-encoded protein if, when aligned with dmaW-encoded protein, at least 85% of its amino acid residues are the same. SEQ ID NO 2 and SEQ ID NO 4 are the most preferred proteins.

DmaW homologs can be the result of natural allelic variation or natural mutation. DmaW homologs of the present invention can also be produced using techniques known in the art including, but not limited to, direct modifications to the protein or modifications to the gene encoding the protein using, for example, classic or recombinant nucleic acid techniques to effect random or targeted mutagenesis.

EXAMPLE Example 1 Obtaining dmaW sequence from N. coenophialum

The following degenerate primers were used to amplify genomic DNA fragments from N. coenophialum by polymerase chain reaction (PCR). A (+) means they correspond in sequence to a portion of mRNA, thus read 5′-3′ on the gene, and a (−) indicates they are reverse complements of a portion of the mRNA and read 3′-5′ on the gene: thus, each PCR involved a combination of a (+) and a (−) primer.

dmaWdeg(+)1: GAR CAR MGN YTN TGG TGG CA

dmaWdeg(+)2: GGN ATH TTY AAR AAR CAY AT

dmaWdeg(−)3: AR NGT CCA NAR RTC YTC CAT

dmaWdeg(−)4: TA NAC YTG NGG YTC NGG CAT

N=A,G,C or T; Y=C or T; R=A or G; M=A or C; H=A, T or C.

Four PCR reactions were performed to amplify fragments from each fungus, using four different primer combinations, dmaWdeg(+)1 and dmaWdeg(−)3, dmaWdeg(+)1 and dmaWdeg(−)4, dmaWdeg(+)2 and dmaWdeg(−)3, dmaWdeg(+)2 and dmaWdeg(−)4. Each 50 microL reaction mixture contained 200ng fungal genomic DNA template, 200 microM each deoxyribonucleotide triphosphate (dATP, dGTP, dTTP and dCTP), 25 mM each primer, 1 X PCR buffer (Perkin-Elmer), and 2.5 units Taq DNA polymerase (AmpliTaq Gold from Perkin-Elmer). Reactions were held at 93 ° C. for 9 min and 95° C. for 3 min, then subjected to 35 cycles of the following profile: 94° C. for 45 s, 53° C. for 45 s, 72° C. for 80 s in a Perkin-Elmer model 2400 Thermal Cycler. After completing these temperature cycles the reactions were incubated 5 min at 72° C., then analyzed by agarose gel electrophoresis.

The resulting amplified genomic fragments were cloned and used as probes of a cosmid library (and thus obtained SEQ ID NO 1 of N. coenophialum dmaW), or the sequences were used as a basis for new primers for anchored single primer PCR (and thus obtained SEQ ID NO 3 of N. coenophialum dmaW).

Clones were sequenced using PE Biosystems Model 310 Genetic Analyzer. DNA sequence analysis was carried out with the DNAsis (Hitachi) and GCG (University of Wisconsin Genetics Computer Group, Madison) sequence analysis packages. Alignment of sequences was done using CLUSTAL W according to Thompson et al., 22 Nucl. Acids Res. 4673 (1994).

Example 2 Construction of knockout mutants

Clones will be constructed containing DNA of each dmaW locus from which all or part of the gene has been deleted, or in which the dmaW has been mutated to a form expected to be inactive. These clones will be used in transformation experiments as described in Tsai et al, 22 Genetics 399 (1992). Transformants will be screened by Southern blot hybridization and polymerase chain reaction to identify those that have had the wild type gene replaced by the mutant form. In endophytes with more than one dmaW copy, such as N. coenophialum, the procedure will be repeated until all active or potentially active copies are replaced with inactive forms. The endophyte, so altered, will be introduced into its natural host, and the loss of ergot alkaloid synthetic properties of the endophyte/grass symbiosis will be determined by standard chemical methods.

Example 3 Identity comparisons

The GAP program of the Wisconsin Genetics Group GCG package was used to compare the original sequence from ATCC 26245 (C. fusiformis) with SEQ ID NO 1 and SEQ ID NO 3, and likewise with the C. purpurea ATCC 20102 dmaW gene (sequenced by the present lab, and identical to the sequence published by Tudzynski et al, cited in Background). Comparisons both with nucleic acid and with amino acid sequences were made, though for hybridization analysis only the nucleic acid identity is of importance. In each case the SEQ ID NO 1 gave slightly higher identity. In nucleotide sequence it was 62.295% identical to the ATCC 26245 and 62.416% to the ATCC 20102 gene. In amino acid sequence its inferred protein product was 61.745% identical to that of the ATCC 26245 and 67.040% to that of the ATCC 20102 gene.

Although the present invention has been fully described herein, it is to be noted that various changes and modifications are apparent to those skilled in the art. Such changes and modifications are to be understood as included within the scope of the present invention as defined by the appended claims.

6 1 1347 DNA Neotyphodium coenophialum 1 atggtaatgg caaagacact ccaccaggaa gtttatcata cccttagcga aacatttgac 60 tttgccaaca atgaccagag gctatggtgg cacagcacgg cgccaatgtt cgaaaagatg 120 ctccaaactg ctaactatag cattgatgct cagtatcgac atctgggcat ttataagagc 180 catgtcattc cttttcttgg tgtctatcct acaagaagtg gcgagcggtg gctaagcatt 240 cttacgagat acggaacccc gtttgagcta agtcttaatt gctcggactc cgtagttcgg 300 tatacatacg agcctattaa cgccgcaact ggcagtcatc tggatccgtt taacactttc 360 gctatctggg aggccctgaa aaagcatatt gagtcccagc caggcataga ccttgaatgg 420 ttttcttact ttaaacaaga gcttacactt gacgcaaacg agtccacgta cctgcactcg 480 caaaacttgg ttaaggaaca gatcaaaact caaaacaagc tcgctttgga ccttaaaggt 540 gacaagttcg tactgaagac ctacatctac cccgaattga agtccgtcgc aactggtaaa 600 tcggtccagg agctcgtgtt tggctccgtc cgcaagctag cgcagaagca caagagtatc 660 cgtcctgcct ttgaaatgct agaagactat gtccagtctc gcaataaatt ctctaccacg 720 gatgacagtc acaatactct attatcttca cgccttctct cttgcgacct gataagtcct 780 accaagtctc gtgtcaagat ctacctcctg gaacgaatgg tctcgttgcc agcgatggaa 840 gatctttgga cgcttggcgg ccgtcgagaa gatcagtcca ctattgaggg attggagatg 900 atccgagaac tttggggtct cctcaacatg tctcctggtt tgcgcgccta ccctgagcct 960 tacttgcccc tcggcgccat tcccaatgag caacttccgt ccatggccaa ttacacctta 1020 caccataatg atcccatacc agaaccgcaa gtgtacttta ctgtgttcgg catgaatgat 1080 atggaggtga ctaatgcact cacgacattc ttcatgaggc atgaatggag cgatatggca 1140 agtaaataca aagcctgcct cagggaatct ttcccgcatc atgattacga agccctgaat 1200 tatatccact cgtacatttc cttctcctac cgaaagaaca agccatattt aagtgtgtat 1260 ctccactcct ttgaaactgg taaatggcca gtgtttcccg aaggtctaat agcatttgac 1320 gcatgccggc gagatttaac ttgttaa 1347 2 448 PRT Neotyphodium coenophialum 2 Met Val Met Ala Lys Thr Leu His Gln Glu Val Tyr His Thr Leu Ser 1 5 10 15 Glu Thr Phe Asp Phe Ala Asn Asn Asp Gln Arg Leu Trp Trp His Ser 20 25 30 Thr Ala Pro Met Phe Glu Lys Met Leu Gln Thr Ala Asn Tyr Ser Ile 35 40 45 Asp Ala Gln Tyr Arg His Leu Gly Ile Tyr Lys Ser His Val Ile Pro 50 55 60 Phe Leu Gly Val Tyr Pro Thr Arg Ser Gly Glu Arg Trp Leu Ser Ile 65 70 75 80 Leu Thr Arg Tyr Gly Thr Pro Phe Glu Leu Ser Leu Asn Cys Ser Asp 85 90 95 Ser Val Val Arg Tyr Thr Tyr Glu Pro Ile Asn Ala Ala Thr Gly Ser 100 105 110 His Leu Asp Pro Phe Asn Thr Phe Ala Ile Trp Glu Ala Leu Lys Lys 115 120 125 His Ile Glu Ser Gln Pro Gly Ile Asp Leu Glu Trp Phe Ser Tyr Phe 130 135 140 Lys Gln Glu Leu Thr Leu Asp Ala Asn Glu Ser Thr Tyr Leu His Ser 145 150 155 160 Gln Asn Leu Val Lys Glu Gln Ile Lys Thr Gln Asn Lys Leu Ala Leu 165 170 175 Asp Leu Lys Gly Asp Lys Phe Val Leu Lys Thr Tyr Ile Tyr Pro Glu 180 185 190 Leu Lys Ser Val Ala Thr Gly Lys Ser Val Gln Glu Leu Val Phe Gly 195 200 205 Ser Val Arg Lys Leu Ala Gln Lys His Lys Ser Ile Arg Pro Ala Phe 210 215 220 Glu Met Leu Glu Asp Tyr Val Gln Ser Arg Asn Lys Phe Ser Thr Thr 225 230 235 240 Asp Asp Ser His Asn Thr Leu Leu Ser Ser Arg Leu Leu Ser Cys Asp 245 250 255 Leu Ile Ser Pro Thr Lys Ser Arg Val Lys Ile Tyr Leu Leu Glu Arg 260 265 270 Met Val Ser Leu Pro Ala Met Glu Asp Leu Trp Thr Leu Gly Gly Arg 275 280 285 Arg Glu Asp Gln Ser Thr Ile Glu Gly Leu Glu Met Ile Arg Glu Leu 290 295 300 Trp Gly Leu Leu Asn Met Ser Pro Gly Leu Arg Ala Tyr Pro Glu Pro 305 310 315 320 Tyr Leu Pro Leu Gly Ala Ile Pro Asn Glu Gln Leu Pro Ser Met Ala 325 330 335 Asn Tyr Thr Leu His His Asn Asp Pro Ile Pro Glu Pro Gln Val Tyr 340 345 350 Phe Thr Val Phe Gly Met Asn Asp Met Glu Val Thr Asn Ala Leu Thr 355 360 365 Thr Phe Phe Met Arg His Glu Trp Ser Asp Met Ala Ser Lys Tyr Lys 370 375 380 Ala Cys Leu Arg Glu Ser Phe Pro His His Asp Tyr Glu Ala Leu Asn 385 390 395 400 Tyr Ile His Ser Tyr Ile Ser Phe Ser Tyr Arg Lys Asn Lys Pro Tyr 405 410 415 Leu Ser Val Tyr Leu His Ser Phe Glu Thr Gly Lys Trp Pro Val Phe 420 425 430 Pro Glu Gly Leu Ile Ala Phe Asp Ala Cys Arg Arg Asp Leu Thr Cys 435 440 445 3 1353 DNA Neotyphodium coenophialum 3 atggtattgg caaagacact ccaccaggaa gtttatcaaa ccctcagcga aacatttgac 60 tttgccaaca atgaccagag gctatggtgg cacagcacgg cgccaatgtt ccaaaagata 120 ctccaaactg ctaactatag catttatgct cagtatcaac atctgagcat ttataaaagc 180 catatcattc cttttcttgg tgtctatcct acaagaagtg gcgagcggtg gctaagcatt 240 cttacgagat acggaacccc gtttgagcta agtcttaatt gctctgactc catagttcgg 300 tatacatacg agcctattaa cgccgcaact ggcagccatc tggatccgtt caacactttc 360 gctatctggg aggctctaaa aaagcttata gattcccagc caggcataga ccttcaatgg 420 ttttcctact ttaaacaaga gcttacactt gacgcaaacg agtccacgta cctgcactct 480 caaaacttgg tcaaggaaca gatcaaaact caaaacaagc tagcgttaga ccttaaaggt 540 gacaagttcg tactcaagac ctacatctac cccgaattga agtccgtcgc aactggtaaa 600 tcggtccagg agcttgtgtt tggctccgtc cgcaagctag cgcagaagca taagagtatc 660 cgtcctgcct ttgaaatgct agaagactat gtccagtctc gcaataaagt ccctaccacg 720 gatgacagtc acaatactcc attatcttca cgccttctct cttgcgacct ggtgagtcct 780 accaagtctc gtgtcaagat ctacctcctg gaacgaatgg tctcgttgcc agcgatggaa 840 gatctttgga cgcttggcgg ccgtcgagaa gatcagtcca ctattgaggg attggagatg 900 atccgagaac tttggggtct ccttaacatg tctcctggtt tgcgcgccta ccctgagcct 960 tacttgcccc tcggcgccat tcccaatgag caacttccgt ccatggccaa ttacacctta 1020 caccataatg atccgatacc agaaccgcaa gtgtacttta ctgtgttcgg catgaatgat 1080 atggaggtga ctaatgcact cacgaaattc ttcatgaggc atgaatggag cgatatggca 1140 agtaaataca aagcctgcct tagggaatct ttcccgcatc ataattacga agccctaaat 1200 tatatccact cgtacatttc cttctcctac cgaaataaca agccatattt aagtgtgtat 1260 ctccactcat ttgaaactgg tgaatggcct gtgtttcccg aaggtctaat agcttttgac 1320 ggatgccggc gagatttaac ttgttataag tag 1353 4 450 PRT Neotyphodium coenophialum 4 Met Val Leu Ala Lys Thr Leu His Gln Glu Val Tyr Gln Thr Leu Ser 1 5 10 15 Glu Thr Phe Asp Phe Ala Asn Asn Asp Gln Arg Leu Trp Trp His Ser 20 25 30 Thr Ala Pro Met Phe Gln Lys Ile Leu Gln Thr Ala Asn Tyr Ser Ile 35 40 45 Tyr Ala Gln Tyr Gln His Leu Ser Ile Tyr Lys Ser His Ile Ile Pro 50 55 60 Phe Leu Gly Val Tyr Pro Thr Arg Ser Gly Glu Arg Trp Leu Ser Ile 65 70 75 80 Leu Thr Arg Tyr Gly Thr Pro Phe Glu Leu Ser Leu Asn Cys Ser Asp 85 90 95 Ser Ile Val Arg Tyr Thr Tyr Glu Pro Ile Asn Ala Ala Thr Gly Ser 100 105 110 His Leu Asp Pro Phe Asn Thr Phe Ala Ile Trp Glu Ala Leu Lys Lys 115 120 125 Leu Ile Asp Ser Gln Pro Gly Ile Asp Leu Gln Trp Phe Ser Tyr Phe 130 135 140 Lys Gln Glu Leu Thr Leu Asp Ala Asn Glu Ser Thr Tyr Leu His Ser 145 150 155 160 Gln Asn Leu Val Lys Glu Gln Ile Lys Thr Gln Asn Lys Leu Ala Leu 165 170 175 Asp Leu Lys Gly Asp Lys Phe Val Leu Lys Thr Tyr Ile Tyr Pro Glu 180 185 190 Leu Lys Ser Val Ala Thr Gly Lys Ser Val Gln Glu Leu Val Phe Gly 195 200 205 Ser Val Arg Lys Leu Ala Gln Lys His Lys Ser Ile Arg Pro Ala Phe 210 215 220 Glu Met Leu Glu Asp Tyr Val Gln Ser Arg Asn Lys Val Pro Thr Thr 225 230 235 240 Asp Asp Ser His Asn Thr Pro Leu Ser Ser Arg Leu Leu Ser Cys Asp 245 250 255 Leu Val Ser Pro Thr Lys Ser Arg Val Lys Ile Tyr Leu Leu Glu Arg 260 265 270 Met Val Ser Leu Pro Ala Met Glu Asp Leu Trp Thr Leu Gly Gly Arg 275 280 285 Arg Glu Asp Gln Ser Thr Ile Glu Gly Leu Glu Met Ile Arg Glu Leu 290 295 300 Trp Gly Leu Leu Asn Met Ser Pro Gly Leu Arg Ala Tyr Pro Glu Pro 305 310 315 320 Tyr Leu Pro Leu Gly Ala Ile Pro Asn Glu Gln Leu Pro Ser Met Ala 325 330 335 Asn Tyr Thr Leu His His Asn Asp Pro Ile Pro Glu Pro Gln Val Tyr 340 345 350 Phe Thr Val Phe Gly Met Asn Asp Met Glu Val Thr Asn Ala Leu Thr 355 360 365 Lys Phe Phe Met Arg His Glu Trp Ser Asp Met Ala Ser Lys Tyr Lys 370 375 380 Ala Cys Leu Arg Glu Ser Phe Pro His His Asn Tyr Glu Ala Leu Asn 385 390 395 400 Tyr Ile His Ser Tyr Ile Ser Phe Ser Tyr Arg Asn Asn Lys Pro Tyr 405 410 415 Leu Ser Val Tyr Leu His Ser Phe Glu Thr Gly Glu Trp Pro Val Phe 420 425 430 Pro Glu Gly Leu Ile Ala Phe Asp Gly Cys Arg Arg Asp Leu Thr Cys 435 440 445 Tyr Lys 450 5 1908 DNA Neotyphodium coenophialum 5 gcattgctac ttcgctaaga agttttcttt taagttgtgt agggatttat tggatgaaac 60 cttagctagt tggctaataa tcttggaggc taggcagcaa aaccctgatt cttactatgc 120 tacatgtata atagacttcc tcagatatta atttcaaacc atgtttgcct gttagttctc 180 tctagcgcaa aggtgacttg ttagaccaca atttgttcaa tctttaactg tatcaaagaa 240 acagacaggg ctattacgct cgtcctcttc ttcacaatgg taatggcaaa gacactccac 300 caggaagttt atcataccct tagcgaaaca tttgactttg ccaacaatga ccagaggcta 360 tggtggcaca gcacggcgcc aatgttcgaa aagatgctcc aaactgctaa ctatagcatt 420 gatgctcagt atcgacatct gggcatttat aagagccatg tcattccttt tcttggtgtc 480 tatcctacaa gaagtggcga gcggtggcta agcattctta cgagatacgg aaccccgttt 540 gagctaagtc ttaattgctc ggactccgta gttcggtata catacgagcc tattaacgcc 600 gcaactggca gtcatctgga tccgtttaac actttcgcta tctgggaggc cctgaaaaag 660 catattgagt cccagccagg catagacctt gaatggtttt cttactttaa acaagagctt 720 acacttgacg caaacgagtc cacgtacctg cactcgcaaa acttggttaa ggaacagatc 780 aaaactcaaa acaagctcgc tttggacctt aaaggtgaca agttcgtact gaagacctac 840 atctaccccg aattgaagtc cgtcgcaact ggtaaatcgg tccaggagct cgtgtttggc 900 tccgtccgca agctagcgca gaagcacaag agtatccgtc ctgcctttga aatgctagaa 960 gactatgtcc agtctcgcaa taaattctct accacggatg acagtcacaa tactctatta 1020 tcttcacgcc ttctctcttg cgacctgata agtcctacca agtctcgtgt caagatctac 1080 ctcctggaac gaatggtctc gttgccagcg atggaagatc tttggacgct tggcggccgt 1140 cgagaagatc agtccactat tgagggattg gagatgatcc gagaactttg gggtctcctc 1200 aacatgtctc ctggtttgcg cgcctaccct gagccttact tgcccctcgg cgccattccc 1260 aatgagcaac ttccgtccat ggccaattac accttacacc ataatgatcc cataccagaa 1320 ccgcaagtgt actttactgt gttcggcatg aatgatatgg aggtgactaa tgcactcacg 1380 acattcttca tgaggcatga atggagcgat atggcaagta aatacaaagc ctgcctcagg 1440 gaatctttgt aagtgatatc ccagctctca cattgcatga caagagttac taacataaaa 1500 atcgcttggc agcccgcatc atgattacga agccctgaat tatatccact cgtacatttc 1560 cttctcctac cgaaagaaca agccatattt aagtgtgtat ctccactcct ttgaaactgg 1620 taaatggcca gtgtgtaagt tttccaatga taatgacaat gcaatgcgcg aagggagtgg 1680 gcttctaata ctattgacta tagttcccga aggtctaata gcatttgacg catgccggcg 1740 agatttaact tgttaagtag atctgctatg gcaataagta acctttatgc acagtacgtg 1800 taatgcagat tatgaaaaga ggagacatgt aaatgcagca acaaccctag taaccaaaca 1860 aaactagtaa cgaaacaaaa tgctacgatc tttagtttgt gtttaaaa 1908 6 1598 DNA Neotyphodium coenophialum 6 attccgctcg tcctcttctt cacaatggta ttggcaaaga cactccacca ggaagtttat 60 caaaccctca gcgaaacatt tgactttgcc aacaatgacc agaggctatg gtggcacagc 120 acggcgccaa tgttccaaaa gatactccaa actgctaact atagcattta tgctcagtat 180 caacatctga gcatttataa aagccatatc attccttttc ttggtgtcta tcctacaaga 240 agtggcgagc ggtggctaag cattcttacg agatacggaa ccccgtttga gctaagtctt 300 aattgctctg actccatagt tcggtataca tacgagccta ttaacgccgc aactggcagc 360 catctggatc cgttcaacac tttcgctatc tgggaggctc taaaaaagct tatagattcc 420 cagccaggca tagaccttca atggttttcc tactttaaac aagagcttac acttgacgca 480 aacgagtcca cgtacctgca ctctcaaaac ttggtcaagg aacagatcaa aactcaaaac 540 aagctagcgt tagaccttaa aggtgacaag ttcgtactca agacctacat ctaccccgaa 600 ttgaagtccg tcgcaactgg taaatcggtc caggagcttg tgtttggctc cgtccgcaag 660 ctagcgcaga agcataagag tatccgtcct gcctttgaaa tgctagaaga ctatgtccag 720 tctcgcaata aagtccctac cacggatgac agtcacaata ctccattatc ttcacgcctt 780 ctctcttgcg acctggtgag tcctaccaag tctcgtgtca agatctacct cctggaacga 840 atggtctcgt tgccagcgat ggaagatctt tggacgcttg gcggccgtcg agaagatcag 900 tccactattg agggattgga gatgatccga gaactttggg gtctccttaa catgtctcct 960 ggtttgcgcg cctaccctga gccttacttg cccctcggcg ccattcccaa tgagcaactt 1020 ccgtccatgg ccaattacac cttacaccat aatgatccga taccagaacc gcaagtgtac 1080 tttactgtgt tcggcatgaa tgatatggag gtgactaatg cactcacgaa attcttcatg 1140 aggcatgaat ggagcgatat ggcaagtaaa tacaaagcct gccttaggga atctttgtag 1200 gtgatatcct agttctcaca ttgcatgaca agaattacta acatataaaa atcgcttggc 1260 agcccgcatc ataattacga agccctaaat tatatccact cgtacatttc cttctcctac 1320 cgaaataaca agccatattt aagtgtgtat ctccactcat ttgaaactgg tgaatggcct 1380 gtgtgtaagt ttccaatgat aatgacaatg caatgcgcga agggaatggg cttctaatac 1440 tattaattgt agttcccgaa ggtctaatag cttttgacgg atgccggcga gatttaactt 1500 gttataagta gatctggcta tggcaataag taaccctcat gcacagtacg tgtaaggcag 1560 attatgaaga gagaagacag ttagttgcag caataacc 1598

Claims

1. An isolated nucleic acid molecule, wherein said nucleic acid molecule comprises a nucleic acid sequence selected from the group consisting of:

(a) a nucleic acid molecule encoding a dimethylallyltryptophan synthase (DmaW molecule) which has more than 70% identity to a molecule selected from the group consisting of SEQ ID NO 1 and SEQ ID NO 3, and wherein said identity can be determined using the DNAsis computer program and default parameters;
(b) a nucleic acid molecule selected from the group consisting of: a nucleic acid molecule which encodes a DmaW amino acid molecule selected from the group consisting of: SEQ ID NO 2; and SEQ ID NO 4; and
(c) a nucleic acid molecule fully complementary to a nucleic acid molecule selected from the group consisting of: a nucleic acid molecule of (a); and a nucleic acid molecule of (b).

2. A knockout construct of a dmaW molecule of claim 1.

3. A vector comprising a knockout construct of claim 2.

4. A fungus comprising a knockout construct of claim 2.

5. A seed comprising a fungus of claim 4.

6. An embryo comprising a fungus of claim 4.

7. A plant comprising a fungus of claim 4.

8. A plant of claim 7, which is a forage grass.

9. A plant of claim 8, which is a fescue.

10. A plant of claim 9, which is a Festuca arundinacea.

11. A method to express DmaW in a cell, comprising transforming a cell with a molecule of claim 1; and incubating said cell under such conditions so as to cause expression of DmaW.

12. A method to identify endophytes that contain or lack a dmaW gene, comprising contacting a nucleic acid molecule of claim 1 with DNA of a sample endophyte under l×SSC and 0% formamide at about 56° C. hybridization wash conditions, and determining if said endophyte contains or lacks the dmaW gene based on the results of the hybridization reaction.

13. A method of claim 12, wherein said sample endophyte is used in commercial plants selected from the group consisting of forage, pasture, turf, land reclamation, and soil conservation.

14. A method for producing increased amount of ergot alkaloids, comprising expressing the nucleic acid molecule according to claim 1 in a host fungal cell, so the copy number of messenger RNA derived from transcription of said nucleic acid molecule is increased, and allowing said host fungal cell to grow under appropriate growth conditions, which causes increased production of ergot alkaloid.

15. The isolated nucleic acid molecule according to claim 1, wherein said nucleic acid molecule encoding a DmaW molecule has more than 75% identity to the nucleic acid molecule having the sequence set forth in SEQ ID NO: 1 or SEQ ID NO:3.

16. The isolated nucleic acid molecule according to claim 1, wherein said nucleic acid molecule encoding a DmaW molecule has more than 80% identity to the nucleic acid molecule having the sequence set forth in SEQ ID NO:1 or SEQ ID NO:3.

17. The isolated nucleic acid molecule according to claim 1, wherein said nucleic acid molecule encoding a DmaW molecule has more than 85% identity to the nucleic acid molecule having the sequence set forth in SEQ ID NO:1 or SEQ ID NO:3.

18. The isolated nucleic acid molecule according to claim 1, wherein said nucleic acid molecule encoding a DmaW molecule has more than 90% identity to the nucleic acid molecule having the sequence set forth in SEQ ID NO:1 or SEQ ID NO:3.

19. The isolated nucleic acid molecule according to claim 1, wherein said nucleic acid molecule encoding a DmaW molecule has more than 95% identity to the nucleic acid molecule having the sequence set forth in SEQ ID NO:1 or SEQ ID NO:3.

Referenced Cited
Other references
  • Gebler, et al., 114 J. of the American Chemical Society 7354 (1992).
  • Tsai, et al., 216 Biochem & Biophys Res Comm 119 (1995).
  • Tudzynski, et al., 261 Molec Gen Genet 133 (1999).
  • Gebler et al., 296 Archives of Biochemistry and Biophysics 308 (1992).
  • Tudzynski,et al., 103 Mycological Research 1044 (1999).
  • Arntz et al. (1997), Current Genetics, vol. 31(4):357-360, 1997.
Patent History
Patent number: 6335188
Type: Grant
Filed: Mar 3, 2000
Date of Patent: Jan 1, 2002
Assignee: University of Kentucky Research Foundation (Lexington, KY)
Inventors: Christopher L. Schardl (Lexington, KY), Jinghung Wang (Lexington, KY)
Primary Examiner: Rebecca E. Prouty
Assistant Examiner: Manjunath N. Rao
Attorney, Agent or Law Firm: McDermott, Will & Emery
Application Number: 09/518,657